This invention relates to a machine for inserting ties on a railroad track and a method of using such a machine. More specifically, this invention relates to a machine which also removes old ties from a railroad track road bed.
In order to maintain railroad tracks in safe operating conditions, it is necessary to replace the ties periodically. The ties (made of wood, metal or concrete) underneath the rails tend to wear out after an extended period of use.
Various machines for removing and/or inserting railroad ties into the railroad track road bed (hereafter "road bed") have been developed.
Among the prior machines for replacing ties are the machines disclosed by the following patents:
______________________________________ U.S. Pat. No. Inventor Issue Date ______________________________________ 3,780,664 Holley et al. December 25, 1973 3,964,397 Dieringer et al. June 22, 1976 4,392,433 Nyland July 12, 1983 4,809,614 Theurer et al. March 7, 1989 ______________________________________
The Holley et al patent shows a machine for inserting ties beneath a railroad track having a pantograph system to control the orientation of a tie clamp which is used for manipulating the tie. As common with many types of machines for removing ties, the arrangement includes rail clamps to secure the machine to the rail and a jacking system for supporting the machine on the ground while using the rail clamps to lift the rails to more easily remove or insert the tie disposed below the rail.
The Dieringer et al patent shows a tie handling machine having an inserter with a tie clamp and a boom for insertion of new ties. The new ties are laid upon the rails in advance of the machine.
The Nyland patent shows a backhoe type tie remover/inserter. An articulated arm at one end of the machine is used to manipulate ties. The other end of the machine has a loader bucket as commonly used on regular backhoes. The machine has tractor wheels for running on the road and a second set of wheels for rolling along a railroad track. Vertical "outrigger" jacks may be moved horizontally and used to support the vehicle as best shown at FIG. 6. Rail clamps may be used in combination with the vertical jacks in order to raise the rail for making it easier to insert or remove a tie from a particular portion of the track.
The Theurer et al patent shows a tie gang apparatus and system wherein a number of individual tie exchanging devices are operated substantially simultaneously at different track sections. The speed of the process is enhanced by the tandem arrangement of tie withdrawing and inserting devices.
Although prior tie inserter and/or remover machines have been generally useful, they have been subject to one or more of a number of disadvantages.
Some prior tie inserter vehicles insert new ties which have been previously deposited on the rails in advance of the vehicle. This is generally advantageous in that it is usually easier and quicker to pick up a tie laying upon the pair of rails then to pick up a tie which is deposited to the side of the road bed. However, depositing the ties upon the rail generally prevents one from using a tandem arrangement whereby different tie insertion vehicles operate upon different sections or zones of the road bed. In other words, a vehicle or device moving in front of the tie inserter can deposit the ties upon the rails, but this will allow only a front tie inserter vehicle to make use of the ties. Any second or following tie inserter vehicle will be separated from the source of the ties and the ties themselves by the front tie inserter vehicle.
Although one could in theory have a tandem arrangement of tie inserter vehicles wherein ties are placed upon the rails by a first source of ties (usually a flat car or cars having bundles of ties together with a crane or other arrangement for unloading the ties) in front of the first tie replacing vehicle and a second source of ties in between the first and second tie replacing vehicles, this increases the number of the machines needed for the tie gang operation and increases the cost and complexity of the operation.
One way to avoid the difficulty in providing tandem operation of tie insertion vehicles whereby two or more tie insertion vehicles operate simultaneously in different sections or zones of the road bed, is to place the ties to the side of the rail. In that fashion, the first tie inserter vehicle may move along the rail to its section, while bypassing the ties disposed at the side of the road bed, which ties may then be used by a second or following tie inserter vehicle. However, it is usually more difficult, time-consuming, and complex to provide an arrangement whereby a tie inserter vehicle picks up ties from the side of a road bed.
Another disadvantage of vehicles and mechanisms which are commonly used for tie insertion and tie removal is that they often require a first complex series of operations to remove an old tie followed by a second series of complex operations to insert a new or replacement tie.
A further disadvantage of numerous prior tie inserters is that an operator must perform relatively complex operations in order to clamp the new tie.
A further disadvantage of numerous prior tie inserter devices and systems will be more readily understood after a brief discussion of the procedures used for tie replacement. The tie replacement is accomplished by a tie gang which includes numerous machines which move along the rail. It should be noted that it is common to selectively replace only some of the ties. For example, one might replace only every third or fourth tie in a particular region. A spike pulling device or vehicle is used to pull spikes from the tie plates corresponding to ties which are to be replaced. A spike collecting device or vehicle could be used to collect the pulled spikes. A ballast clearing device is commonly used to make it easier to remove old ties within the road bed. A machine or vehicle lifts the rails at a portion of the track while pulling out an old tie disposed under that portion. The tie plates corresponding to the tie which is being replaced are usually replaced because the tie plates drop free of the rails upon lifting of the rails. After new ties and tie plates have been inserted, a machine is used for tamping ballast and a vehicle or device is used for spiking the replacement tie plates into the replacement ties. Of course, a vehicle or machine must be used to supply the replacement ties to the vehicle or machine which is inserting the replacement ties. Various other machines could be used as part of the overall process.
The complexity of the above process is substantially increased by the common requirement for removing old tie plates, which fall when the rail is lifted, and inserting and properly placing new tie plates. The increased complexity, cost, and time is disadvantageous in that the old tie plates are usually in quite acceptable condition. Indeed, often replacement tie plates are simply recycled old tie plates.
The invention of the Madison and Newman application referenced above avoided or minimized several of the problems discussed above. However, that tie replacement technique requires about 12 feet of clearance to the side of a rail. This may work fine at most locations, but some places along a railroad track do not have sufficient clearance. Further, the requirement for moving ties over the top of an operator cab and, especially, the mounting of the tie inserter boom above the main frame on that design meant that one had to be careful to maintain the stability of the vehicle.